Method of combustion control and apparatus therefor



Jan, 13, 1925.

C. MESSICK METHOD OF OOMBUSTION CONTROL AND APPARATUS THEREFOR 1922 2 Sheets-Sheet l Filed July 13 IWI IUI nnnnnflallnrnz Jan. 13?, 1925. 1,522,898

, C. MESSICK METHOD OF COMBUSTION CONTROL AND APPARATUS THEREFOR Filed July 1s, 1922 2 sne'etsfsheet 2 I ljuvlh Patented jan. 13,v 1925.

CHARLES MESSICK, OF BRENTWOOD, NEW YORK.

METHOD OF COMBUSTIO-N CONTROL AND APPARATUS THEREFOR.

Application led July 13, 1922. Serial No. 574,759.

To all whom it may concern.'

Be it known `that I, CHARLES Mnssrcn, a citizen of the United States, residing at Brentwood, in the county of Sulfolk and State of New York, have invented certain new and useful Improvements in Methods of Combustion Control and Apparatus Therefor, of which the following is a description.

An object of my invention is to provide an improved method to control combustion, particularl f of coal, or other solid fuel, so that the rate of combustion may be edectually and quickly varied and, if required, maintained automatically at a very low rate.

Another object is to provide an improved apparatus in which my method may be pracp ticed, which will be reliable and substantially as low in first cost and maintenance as the apparatus which it is designed to replace.

Another objectof my invention is to combine a temperature controlled means with a valve in a passage connecting the ash pit and diving flue of a furnace and also, if desired, to control the draft intake by said means, whereby increased efficiency of control of the fire may be effected.

Other objects may appear from the following detail description of a specific application of my methodl and a specific form of appiratus in which the method may be practice The preferred form of my improved method consists of connecting the chimney suction permanently to the top of therpre through the combustion chamber and fire passages which terminate at or below the level of the grate bars. The chimney suction being opened into the ash-pit at the level of the grate bars when it is desired to decelerate combustion and if necessary com pletely smother it without breaking the vacuum created by the suction of the chimney, thus at all times avoiding gas leakage.

In regulating and controlling the fire by this method any leakage of the furnace is inward and in the preferred form of the apparatus, I arrange the combustion chamber, tire passages, and damper so that they will be lall self-cleaning, the collected soot and dust; automatically falling into the ash-pit. The necessity for so-called clean-out openings is thus eliminated.

The apparatus of my preferred construction is designed to be built so that even though it be operated for years no accumulation of soot or dust will occur, eitherin the may be thoroughly shaken,

ma other Solid fuel.

furnace proper or in the standpipe of the Hue connecting the furnace to the chimney, and this is of very real importance, for the reason that neglect to remove dust and soot from the horizontal furnace ues through the clean-outs in the conventional type of apparatus frequently impairs their` eilicienc'y to a very considerable extent. 1 The drawings show a small hot water heating furnace for a private house and when in operation at full load in cold weather this heater may be yexpected to give resultsl equivalent to the best furnaces of conventional type and similar size and perhaps a slightly higher efciency owing to the imroved arrangement of the fire passages.

When the conventional furnace is operated at very light load in down; such for instance, as opening the feed door, letting ashes accumulate on top of the grates, or even .putting them on top of the fire, so as to decrease the draft. Under such conditions of light load my improved method of control and superior design of apparatus exhibits much higher fuel eiciency and may also be operate-d with less fuel than the conventional type of heater,

as well as being operated with much less personal attention. This is because the fire can be kept as low as need be without the opening of the feed door, clogging the draft with ashes, etc.

With my improved method of combustion control, and my improved apparatus, the fire heaped up with fresh coal and left for several days under thermostatic control and without personal attention; the combustion only proceeding at a rate sutii'cient to supply the required heat and no more. With the conventional method and apparatus this cannot be done as well for the conventional dampers are less eective. A

With my method and apparatus I am able to approximate the very excellent economy of an automatic gas water heater, for I can quickly reduce an intensely hot fire to a very dull one and yet waste no fuel, whereas with a conventional coal impracticable. v-

Draft'is essential tb the burning of coal Natural draft is far more common than forced draft. Natural draft operates ciple and one of the reasons for the superlor mild weather, all sorts; of expedients are resorted to to keep the fire burning furnace this 1sl `on the thermo-Siphon prinefciency of my method and apparatus is that I never have to open the feed door to check my lire. Opening the feed door lets in cold airgwhich cools the chimney, and cooling the chimney reduces the available draft when a sudden demand for more heat occurs. My chlmneys always hot and I can therefore `always accelerate combustion rapidly.

My apparatus may be likened to an inverted U-tube, having equal legs which both open into an ash-pit when the fire is damped,

' better results are improved \nevertl1eless,

the 'ash-pit being at all times evacuated by the chimney draft and thus the escape of gas into the room prevented. :There is no circulation of air up through the re when my damper is open, even though there be leaks in the ashpit,--etc., for both legs of the U.- tube open into thechimney draft evacuated ash-pit at they same level. However, it should be understood that there must be permitted at all .times a slight venting up the chimney of the waste gases to keep the lirev alive even though burning very slowly.

Continuing the analogy, when the fire is to Yburn briskly, the ashfpit below the leg of the inverted U-tube which includes the fire is opened to atmosphere by a conventional draft flap and the other leg is closed to the ash-pit by the closing of the damper, thus there is a circulation `of fresh air up through the fire, out through the. chimney, and rapid combustion occurs.

While the damper and the draft liap may be operated independently and by hand, obtained when they are coupled together and controlled by a conventional thermostatic regulator. The heat is thus supplied only as required and a very high over-all efficiency obtained.

Whenthe several factors are thus combined, they cooperate to providea greatly flexibility and economy of solid fuel combustion as compared to the conventional method and apparatus, particularly when only a small amount of heat is required, or when a brisk' fire should be quickly reduced to a very low lire.

While it is preferable to include all the steps of my method and the features of the apparatus of my preferred construction, any of the individual and l' novel steps of my method, or features of my apparatus, sin l or in combination ma be beneficially aplied to conventional ,prae tice, the scope of my invention being measured by my appended claims.

Referring to the accompanying drawings:

Fig. 1 is a front elevation of a vertical sectional hot water boiler provided with my combustion control devices, and in which my method may be practiced;

Fig. 2 is a side elevation of the boiler of Fig. 1, partly broken away and in section;

Fig. 3 1s a cross-section Yof the boiler taken on the line 3-3 of Fig. 2-L

Fig. 4 .is a view of the starting damper of the boiler taken on the line4-4 of'Fig. 2;

Figs. 5, 6, 7 y and 8, are diagrammatic illustrations of my system four different conventional types of boilers.

Referring to Figs. 1 to '4: Numeral 1 indicates a `base which forms an ashit 3, and supports the grates 5 and the holler 7. Within the boiler 7 are formed the fire-pot 9 containing a fire-body 10, and the combustion chamber 11 from which the products df combustion normally travel through the ports 13-13 into the diving viue 15. This diving Hue 15 is water jacketed by sections of the boiler as indicated, to increase the heating surface and after descending through it the products of comb up the ue pipe 16, which is designed to be connected to the chimney.

The arrows of Figs. 2 and 3 indicate the ow of the products of combustion after the fire is lighted and in normal operation.

When the boiler 7 is cold and re is to b kindled, the vstarting damper 17 is opened by being thrust to the right from the position shown in Fig. 4. After the fire" is as applied to ustion pass burning brightly and the chimney heated so as to draw well, this damper 1-7 is returned to the indicated position, where it is permitted to' remain as, long as the -fire is alight. Should this damper 17 be left open continuously, the control of the fire would be less perfect; particularly when little heat was required, as the draft cannot be completely neutralized by the controller 35 (to e described later) when damper 17 is open. -'ll1eoretically, the rapidity of combustion can be perfectly controlled in the conventiona type of furnace or boiler. Owin to the unfinished castings, which are use to eliminate thev cost of machine work and to the uneven thermal expansion, or contraction, between the various parts of the boiler, however, such controlcannot be effected in practice. My method of control is designed to be practiced in apparatus made of unfinished castings, to tolerate leakage, andr yet give perfectN control. v y y Referring to Fig. 2, a thermostat 19, designed to be operated byichange ottemperature of the water and positioned atl the top of the boiler 7 is provided with an arm having a weight 33 to hold it normallyl the controller closed against the weight of 35, The controller 35, which is merely a hinged flap, is held up and closed in the indicated manner by the chainl 29, acting through the lever 37, which is attached'toth loo lli)

externally projecting pivotal portion 39 of the controller 35.

The controller 35 is designed to move in the direction of the arrow 41 of Fig. 2. When the controller 35 is opened in `this direction it permits free circulation between the air in the ash-pit 3 and the products of combustion ascending into the flue 16, and destroys the draft through the fire 10. When controller 35 is open, it also permits all the soot which may have collected in the diving flue and the flue 16 to fall by gravityy into the ash-pit 3. The level of the bottom of the diving flue '15, where it com municates with flue pipe 16, with relation to the level of the grates 5, affects the quickness with which the controller 35, when opened, checks the lire. The lower the opening between diving flue 15 and flue pipe 16, the more quickly controller 35 checks the fire, and conversely, the higher the passage from diving flue 15 to flue pipe 16 the more slowly the controller 35 checks the fire. Thus when starting damper 17 is open the controller 35 can only check the fire slowly.

Assuming the fire to be burning normally and the parts to be in the indicated position and the water to become too cool, the thermostat 19 will lower the counter-weight 23 and raise the center of the beam 25. Referring to Fig. 2, where all parts of the apparatus are shown in neutral position, it will be seen that the controller'35 is closed, so that the chain 29 prevents the right-hand end of the beam from rising and compels chain 27 to lift draft flap 31, which permits air to enter beneath the grates 5 and accelerate the fire.

Now' assuming the water to have become too hot, the thermostat 19 lowers beam 25, which first permits the draft fiap 31 to close by gravlty, and the parts to return to the indicated position, after which, as beam 25 continues to descend, the weight ofcontroller 35 causes it to open and destroy the draft through the fire 140, thus quickly decelerating combustion.'

Fig. 5 shows a boiler of the same general type as that described in Figs. 1 to 4, except that the lire passages are longer. The arrow shows the tion.

Fig. 6 shows a conventional -type of boiler in which the diving Hue is external to the boiler proper. The controller is indicated at 61, aclean-out openin 'at 62, and the arrow 63 shows the normal path of the products of combustion.

Fig. 7 shows a small hot water boiler equipped with a conical form of controller valve 70, and the normal path' of theproducts of combustion is indlcated'by 'the arrow 71.

Fig. 8 shows a conventional horizontal lire tube boiler. The arrow 80 indicates the path of the products of combusnormal travel of the products of combustion. The controller is indicated at 81 and the kindling damper at 82.

I do not limit myself 'to the construction shown and my invention is measured. by the appended claims.

I claim:

1. A hot water boiler having an ash pit, provided with a thermostat operated by the temperature of the water, and means operated bythe thermostat to open the ash pit to chimney draft for slow combustion, close thev ash pit to chimney draft for normal combustion, and close the ash pitto chimney draftl and open it to atmosphere for accelerated combustion.

2. A furnace including an ash pit, a `'lire pot, a combustion chamber provided with a diving flue, the fire pot and combustion chamber being enclosed by a space designed to contain a circulating iuid to carry the heat away from said fire pot and combustion chamber for use at a distance, a normally closed chimney connection to the ash pit and thermostatic means, governed by the temperature of the circulating fluid t-o open the connection when combustion is to be decelerated.

3. A furnace including a fire pot and a combustion chamber, an enclosed space surrounding the fire pot and combustion chamber and designed to contain a circulating fluid to carry the heat from the fire pot and combustion chamber away from the furnace for use at a distance, a diving flue from the combustion chamber to a chimney connection and an ash pit also provided with a normally closed chimney connection designed to be opened to decelerate combustion when the circulating iiuid becomes too warm and thermostatic means to open the normally closed chimney connection when combustion is to be decelerated.

4. A furnace in which the combustion of solid fuel may be' effected, provided with a diving flue designed to be connected to a chimney and also provided with an ash pit, a passage connecting thediving ue and the ash pit provided with a valve and a thermostatic device connected to the valve, for the purpose of opening or closing the valve to control the combustion in the furnace.

5. A furnace in which the combustion of solid fuel may be effected, provided with a divingiue designed to be connected to a chimney and also provided with an ash pit having a draft opening and 'means to open or close same, a passage connecting `the diving flue and the ash pit provided with-a valve and a thermostatic device connected to the valve and the means, for the purpose of opening or closing the valve and the means to control' the combustion in the furnace.

CHARLES MESSICK. 

